3. Pleated khaki pants.

"Stay away from those god awful khaki old man pants with the pleats in the front." —ocm09876

Pleats are generally considered unflattering and should be avoided. The extra fold of fabric creates an odd, billowing silhouette that is best avoided if you're on the average to skinny side of pant sizes.

Instead wear: Flat-front, slim-fit chinos.

2. Clothes that don't fit.

Over and over again, we at Business Insider have emphasized fit over everything else when it comes to clothing. We're not kidding. Well-fitting clothing is more flattering no matter what your body type is.

Instead wear: Clothes that fit well. (For suits, our guide is a good place to start.)